A 40-year-old HIV-infected woman developed nausea, vomiting, and epigastric pain and died following her third dose (per study protocol) of interleukin (IL)-2. Her HIV infection was diagnosed in 1996. Her last CD4 cell count was 390/microL, and her viral load was negligible (as of November 28, 1998). She had no known general risk factors for thrombosis other than HIV infection, injection drug abuse, and antiretroviral therapy with indinavir. Abdominal films showed no sign of mechanical obstruction but a generalized gas distention of the bowel, which was suggestive of paralytic ileus. Autopsy revealed dilation of the small bowel with extensive necrosis and hemorrhage involving all the segments. The superior and inferior mesenteric arteries revealed severe atherosclerosis. The stenotic celiac artery was occluded by a recent thrombus at the aortic ostium. Clinicians need to be aware of the potential for thrombosis and accelerated atherosclerosis in HIV-infected patients. Both injection drug abuse and protease inhibitors, such as indinavir, have been shown to be risk factors for thrombosis. However, it is likely IL-2 contributed to the severe thrombosis in this patient, although definitive proof is lacking. An acute awareness of intestinal infarction in HIV-infected patients is warranted.